GM 5.3 Lifters

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Between FB and forums seems like there has been a lot of issues with lifters in these AFM motors. What's everyone's opinion on preventive maintenance on these motors whether it's shorter OCI's, additives, or just running OLM with a top notch oil and keep fingers crossed? Thanks everyone for your input, appreciate it.
 
There isn't anything you can do. It's a design flaw from the get-go. The lifters just aren't strong enough for the design parameters.

The bungled PCV system (that was just recently fixed with a valve cover update), combined with the fairly heavy usage that most of these engines see adds up to failure.

If you bought the truck new, took epic care of it, used only top notch oils, you MIGHT have been able to avoid an issue. Maybe.

To be fair, it's not really as bad of an issue as it seems. Yes, it's common. No, it's not a guarantee. It's like the VVT solenoids on Toyota V6's. Are they common? Yes. Widespread? Hardly. They built hundreds of thousands of those engines just like they built 5.3's as fast as they could move the assembly line.
 
PEA fuel system cleaners, Rislone Concentrate, and Mopar Combustion Chamber Cleaner, made my high mileage 2011 5.3 Silverado AFM run really good.
 
The updated valve covers I believe were being installed on the assembly line the later part of 2011.

GM sells over 40,000 units a month (Silverado/Sierra combined). It's not a big of an issue as the Internet makes it out to be.

Do the math-these motors (with the AFM) started appearing in 2007. As mentioned-just think how many are on the roads.
 
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Don’t try to outsmart the GM engineers. Use only Dexos approved motor oil. No conventional oil, and no 40 weight blends. The Dexo oils come in 0-20, 5-20, and 5-30. Check your manual. If it asks for, 5-30, stick with 5-30.

Now this is me, but I would stick with top tier gasoline, and maybe use the cleaners. What year is the engine?

SF
 
Texas Speed & Performance has an AFM delete kit to make it a normal V8 engine again.
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Originally Posted By: das_peikko
Texas Speed & Performance has an AFM delete kit to make it a normal V8 engine again.
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What he said ^^ - delete the AFM, then tune it off....Problem solved.
 
It's not the end of the world to replace the lifters & delete the AFM altogether, It also allows use of a LS3 Valley Cover that has a oil separator/PCV built-in.

*LS7 Lifters GM part# 12499225
*LS3 Lifter Guides GM part# 12595365 (X4)
*LS3 Valley Cover GM part# 12599296
*L33/5.3L-HO Head Gasket GM part# 12589226 (X2)
*2004 & up LSx Head Bolt kit GM part# 17800568 (X2)
*Upper Engine Cleaner GM part# 88861803 (X2)
*4 foot of 3/8" Trans Cooler Hose (Used to reroute the PCV to the Valley Cover)
*3/8" Vinyl Vacuum plug (To plug the drivers Valve Cover PCV port), I like to use a GM/LS3 piece here but GM doesn't sell them separate from the valve cover.
*ECM Tune to turn off all AFM functions.
*I highly recommend replacing the Exhaust Manifold Bolts with ARP replacements......part# 134-1202

The Upper Engine cleaner is to soak the pistons overnight while the cylinder heads are off.

I do about 1 of these a month on average, Annoying ticks, Misfires & oil consumption are eliminated!!
 
I think I see two water pump gaskets there. Might as well change the water pump if you go that route. From what I heard, if the engine fails you typically lose the contribution of the cylinders it failed on and then the engine doesn’t run well. Then it would be time for the kit. To have a mechanic install that kit looks to me like a couple thousand dollars.

I have not heard of the failures wiping out the engine. Anyone have other info?

SF
 
Originally Posted By: clinebarger
Just to add as I didn't see the post ahead of me....
You DO NOT need to change the Camshaft or remove the Balancer & Front Cover!!!


No but they got the camshaft available for you incase the AFM lifters destroyed the camshaft.
 
Originally Posted By: Snagglefoot
I think I see two water pump gaskets there. Might as well change the water pump if you go that route. From what I heard, if the engine fails you typically lose the contribution of the cylinders it failed on and then the engine doesn’t run well. Then it would be time for the kit. To have a mechanic install that kit looks to me like a couple thousand dollars.

I have not heard of the failures wiping out the engine. Anyone have other info?

SF



Calls for 11.4 hours, I charge $85 per hour.....$969.00
 
Originally Posted By: clinebarger
It's not the end of the world to replace the lifters & delete the AFM altogether,

I do about 1 of these a month on average, Annoying ticks, Misfires & oil consumption are eliminated!!


How much does the parts bill usually come out to ?

SF
 
Originally Posted By: Oil_Flunky
PEA fuel system cleaners, Rislone Concentrate, and Mopar Combustion Chamber Cleaner, made my high mileage 2011 5.3 Silverado AFM run really good.


Yes, new love found for high PEA content fuel cleaners with anythin from the General.
 
Originally Posted By: clinebarger
I do about 1 of these a month on average, Annoying ticks, Misfires & oil consumption are eliminated!!


How often do you see destroyed camshaft lobes from the AFM lifters, which are collapsed, bouncing up and down between the camshaft lobes and the pushrods?
 
Originally Posted By: johnD2
Can anyone recommend a good set of lifters for a rebuild ? 4.8 / 5.3


LS7 style GM part# 12499225......Technically a GM Performance Parts number, Can be had cheap from Summit Racing. If you go to a dealership parts counter.....They will try to sell you each lifter separately for more money.

Same with Head Bolts! Buy the GMPP set 12498545 ('97-'03), You need 2 sets.
 
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